Yellow Hawkweed
Yellow Hawkweed, Meadow Hawkweed, Field Hawkweed, Yellow King-Devil
Hieracium caespitosum Dumort.
Asteraceae (Sunflower Family)
▲ colony of plants in flower
▲ mature flowering plant, showing clustering crowns at base
▲ ▼ inflorescences
▲ ▼ inflorescences showing stiff hairs with black bases on flowering stems and on bracts below inflorescence
▲ ▼ closer view of hairs on flowering stems and leaves
▲ ▼ closer view of hairs on flowering stems and leaves
▲ ▼ colonies of crowns and leaves
▲ ▼ colonies of crowns and leaves
▲ crown base showing short section of rhizome/stolon
Hieracium caespitosum Dumort., Meadow Hawkweed, Yellow Hawkweed, Field Hawkweed, Yellow King Devil: (Bayer Code: HIEAU; US Code HIAU)
- European native, rhizome and stolon-producing, creeping perennial weed that produces leafless to nearly leafless stems 6-30 inches tall above a rosette of clustered leaves; stems have many stiff, outspread hairs, many with darker glands at their base, particularly in upper portion of the stems
- Basal rosette leaves are medium to light green, alternate, with pointed or round-pointed tips; leaves usually covered with many long, stiff, white hairs, but sometimes may be hairless
- Head inflorescences are 0.5 to 1 inch in diameter, dandelion-like, in clusters at tips of usually leafless stems; heads have no disk flowers, but 20-50 or more yellow ray flowers; the yellow “petals" have 4 notches in their flattened tips
- A single row of bracts below the head form a cylindrical to barrel-shape; individual bracts are green, linear, with pointed tips; bracts have a center ridge of black, gland-based hairs; stems just below the heads have the same black hairs
- Flowering is from mid-spring through mid-summer
- After flowering the florets from the head become a globe of white hairs from the pappus (parachute-like hairs) attached to small, brown to black, mature seed/fruit
- Prefers low-fertility, acidic, sandy soils; found in lawns, cultivated fields, pastures, non-crop areas, right-of-ways
- More common in northern Midwest, and is a problem due to the monocultures it develops as it spreads laterally by stolons and rhizomes
- Similar species:
- Orange Hawkweed (Hieracium aurantiacum) looks very similar to yellow hawkweed in leaf shape, growth form and height, except it has orange to red-orange florets in its flower heads
- Tall Hawkweed (Hieracium piloselloides) looks very similar, but has leaves that are hairless except for long white hairs along the leaf edges, and along the midvein on the leaf undersides
- Common Catsear (Hypochaeris radicata) has similar yellow flowers, but has a more branched, open clustering of flower heads, and individual heads have long supporting stalks; also the basal rosette leaf margins of common catsear are widely lobed, not smooth or toothed, as with yellow hawkweed
- Smooth Hawksbeard (Crepis capillaris) has similar, but smaller, yellow flowers, but they are in larger, more open clusters; plus stems and basal leaves are hairless, and basal leaves have deep, pointed lobes, and there are smaller leaves along the flowering stems
- Dandelion (Taraxacum officinale) has similar flowers, but has nearly hairless, deeply toothed rosette leaves, and flowering stems are single, pale green to pinkish, hollow and leafless
(Updated November 25, 2022)